Fluid-flow indicator



' Dec. 13,1927.

A. C. T. ISAAC.:Y

FLUID FLOW INDICATOR Filed oet. 12. 1925 Inventor Archibald CT Isaac- Hs Autor-neg.

Patented Dec. 13), 1927. p

UNITED si'rATlazs` PATENToFrici-z.

Baumann c.

Ell.4 ISAAC,- OF PITTSFIELD, MASSACHUSTTSQASSIGNOR T GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.r

' FLUID-FLOW INnrcA'ron.

Application med' october 12, 1925. serial no. 62,175.

novel and the invention, attention is now directed to said drawing, the description thereof and the appended claims. Referring to the drawing, is a- Venturi tube through which water iows from aconduit 6 in the direction of the arrow. The .tube is provided with the usual Venturi throat 7 and low and high pressure metering ports 8 and 9 respectively. Port 8 lcommunicateswith the interior of a short c lindrical meter casing'10 mounted onthev enturi tube. In the present example the cas-4 ingis cast integral with the tube on one side 2.5 thereof. The casing encloses a pair of expansible, cylindrical metal bellows 11 and.-

12 arranged substantially concentrically with respect to each other and the `casing to resiliently support a movable abutment in the form of a cylindrical diaphragm 13 posi- 4tioned .adjacent theinner end of the casing concentrically therewith.A The diaphragm in the present example is integral with Lne outer bellows 12 forming a bottom wall 85 therefor, .and is .connected with the adjacent end of the inner bellows* through a similar bottom wall 14, with which the latter is provided, soldered or otherwise suitably secured thereto. 40 v'.lhe'op'posite ends of the bellows join a tight fitting cover 15 for the casing, the outer` bellows 12Kbeing provided with la iiange 16 which is secured between a flanged end 17 of' the casing an'd the `cover, and the'inner beli5 lows' llbeing secured to the-cover in a similar manner by a. clamping ring 18 bolted to the inner face of said cover. The jointsbetween the cover, casingl and bellows. are made pressure tight b any -suitable method or means, such as so dering, for example, so that the interior 4of the casmg and of the outer bellows vare hermetically sealed and separated from each other by the diaphragm 13 and the wall yof bellows 12. A The casing`is also in communication with lthe high pressure. metering port 9through a pressure conduit 19 lea'din from said port to the cover end of the' casing and the intev rior of thel outer bellows 12.` With the interior of the casing directly connected with pressure port 8 as hereinbefore stated, diaphragm 13 is thus subjected to the metering v pressure from port 8 on one Side, the lower 'i side in the present example, and to the metering pressure from port 9 on the other side,- the upper side in the present example, and moves in response to the pressure differences set up by the iow in the Venturi tube. Viewed in another aspect, the outer bellows and vthe diaphragm may providing a wall which divides thev casing in to two separate or independent compartments, each of which is in communication with a separate metering port.

With the iiow as indicated, in the direction be considered as of the arrow, a greater pressure exists at v port 9 and abovethe dia hragm than at port 8 and below the diap ragm, with the result that the diaphragm moves 'downwardly to extend the double bellows arrangement until the latter is stressed suiiciently to hold the diaphragm in equilibrium. As

the 'difference in pressure between ports 8 and 9` changes with changes in iow, according to the well known operation of 'a Venturi tube, the diaphragm moves to a new point of equilibrium either upwardly or downwardly in response thereto, thereby 'indicating thev change in flow,`

The range of movement or travel of the diaphragm is determined by the strength of bellows 11 andv 12 and the size of the Ven- 'turi throat 7, and is preferably short so that the bellows an'd casing may be made short y and compact.` It will be seenv that with a .given vdiaphragm and bellows,

the range of travel of the formermay be kept within the desired limits for any range of iiow in the Venturi tube, by the proper choice of the throat s1ze.

The interior of they inner bellows 11 is open to the atmosphere through a central opening 20` in the cover and a bearing housingl 21 surrounding said opening integral with the cover. The-inner bellows forms a well beneaththe bearing housing through which extends a rod 22 connected `at its lower end with the diaphragm center as indicated at 23, and provided with a sharpl pitched screw 24 at its' upper end. The" screw nes within the benin rotates in a bearing, such as ball vbearing operates within a similarly t readed cylinving whereby the abutment f 1S responslve t0 drical nut to rotate the latter in response the pIeSSuI' \Sl1 PPl 1ed t0 the Casing rm to movement ofthe diaphragm, l The nut, sald ports, and lndicatmg means responsive to movement `of the abutment connected 26, ,iitted into' the housing 21 and is. conthelWlth y i v v .A nected with a suitable indicating means for 3. A flow lndlcator having a body comprisindicating the position and movement of the lng a Venturi tube and acasmg integral with. diaphragm as. an indication of the flow. a Wall thereof, L Pmlf'I metering RI'GSSQI'B lIn the present example the nut, carries a ports 1n said wall connected with the lnterlor Y pointer` 27 as an indicating means and the of the easing at oppositeends thereof, ,a .pointer is arranged to swmgjover a'seale movable abutment. 1n the casmg between sald 28 secured to the casing cover. Ay full Scale ends, a pair ofconcentric cyllndmcal beldexflection 0f the pointer ips permitted by pro-` lows connecting said abutment with one end lviding the proper threadpitch in the screw of the casing, the outer bellows and the abuthou-sing and dividing wallbetween the ends 4of the casand nut arrangement. The nut is prevented ment Serving t0 dVdfg the Casing interior from axial movement by being tightly fitted DO WO independent COmPl'tll'leIltS, elch 0f 'in the inner ring of the ball bearing and the bearing is retained in the housing by a re' taining cap 29.

The construction sho`wn provides a com- A pact indicator of few parts,`and one which -v bility, the in Awith a Venturi tube, of a comprises 'no rubber packings, gaskets or the like to cause leakage or sticking of moving parts. It isextremely reliable in operation'and'tle simple construction renders it low in manufacturing cost. The Venturi tube and meter casing are made in one simple castin and providea rugged meter or indicator ody within -which all -operating parts are safely enclosed. Because of its compact, ru ged construction and reliaicator of the lpresent invention Iis well adapted 'for mounting in the cooling water conduits of transformers and the like jrior directly indicating the cooling water To maintain the indicator in operation, no attention is required other than an occa- .sional oiling of the screw 24 and-bearing 26 f which are,convenient1ylocated for this pur- What I claim as new and desire to secure "by 'Leiters Patent of the United sintesis i 1. In a iow indicator, the 'combination n meter casing integral therewlth, a movable diaphragm within the casing an expansible bellows connectmg -the diaphragm with one end of the casing, said bellows and diaphragm dividing the casing, interior into; -two independent compartments, means for supplying' pres- Aeures from the Venturi tube to said con 1part ments, and indicating means connected with the diaphra .2.' In a ow indicator, the combination-- with a. Venturi tube having a high and aiV low pressure metering port in a side wall.

port, a movable abutment Itweeurthelends thereof, means connecting the abutment and the to thereof, of a meter casing mounted on said sidewall in communication at one end' with l one of saidports, a conduit; connecting. the

opposite en of the casing 1n theA casing b provide a ment is actuated in response tothe pressures supplied byl the pressure ports, and indicating meansfconnected with the abutment .to

be moved thereby.` y

4. In a ow indicator, the combination with a tegral therewith, a pair of expansible be ows within the casing arranged one withinA the other, a movable diaphragrimwithin the -casing, each of said bellows g connected at one end with the casing and atl the opposite end with the diaphragm, whereby the after is yieldably su ported with respect to the casing by the ABellows, conduit means connecting the Venturi tube withthe casing to supply metering pressure from said tube to the t casing on op ositov sides of the dia- Venturi tube, of afmeter casin inphragm, whereby t e diaphragm is moved in response to pressure changes, and' indicatin means carried by the casmg and connecte ,with the diaphragm. v

5. In a flow indicator, the combination with a Venturi tubeha a Venturi throat, of a meter casing integra therewith, a pair .of expansible be ows within the Acasing arranged one within the other, a movable dia` phragm'within the casing, each of said bellows bei f" connected at one end rwith the casing an` at theo posite end.' with the diaphragm, whereby t e latter is yieldably suported with respect to the ,casing by the be ows, .a low .pressure metering port in the wall of the Venturi tube connecting the throat thereof with ,the interior of the cas ing, a high ressure metering-port in the'L wall of the -en'turi't'ube connected withl the interior of the outer bellows; a rod which' asses through the interior of the inner belows connected jatv one`endwith the diaphragm to Abe moved thereby, and indicating means actuated by movement of the ,rod connected withvtheopposite end thereof.

-6.- In a ow indicator, thecombination with a Venturi tube having a Venturi throat, of a meter .casin integral therewith, a pair of'expansible cy drical bellows within thearranged substantially concentrically with each other one within the other, a movable diaphragm within the casing, eachY of said bellows being connected at one end with the casing and at the opposite end with the diaphragm, whereby the latter is yieldabiy supported with respect to the casing by the bellows, a low pressure, metering port in the Awall of the Venturi tube connecting the throat thereof with the interior of the casing, a high ressure meteringport in the wail of the enturi tube connected with the .y interior of the outerrjbellows, a rod which v passes through'the' interior of the inner bellows connected at one end with the dia- 15 hragm to be moved thereby, a screw carried y the opposite end of said rod, a nut into which said screw is threaded, a. bearing for l the nut, and indicating means connected with the nut. v

In witness whereof, I have hereunto set my hand this 8th day of October, 1925.

ARCHIBALD C. T.1sA.Ao; 

